2010 AUTUMN Page 127
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TK11855
DCDC Converter, 1ch, Step-up, Inductive
DCDCコンバータ、1ch、昇圧、インダクティブ
Feature
High efficiency 高効率85％
570kHz operation 動作周波数 570kHz
Internal switching transistor スイッチングトランジスタ内蔵
Maximum duty cycle 90% 最大デューティーサイクル 90％
Very small inductor available 小型コイル使用可能
Very small package SON3024-8 0.75mm薄型パッケージ SON3024-8
Operating Voltage Range VOP=2.65 to 16V 動作電圧範囲VOP=2.65~16V
Operating Temp. Range TOP=-30 to +85°C 動作温度範囲TOP=-30~+85°C
Power Dissipation PD=600mW 許容消費電力PD=600mW
Characteristics
Part Name Number of
Current Stabilizer
fOSC Number of LED in
serial connection
ILED Max
TK11855 - 570kHz 2 to 4 LED 20mA
Ordering Guide, Marking
Part Name Ordering Name Marking Description Order
Size
TK11855 TK11855FTL-GH AB0
LOT
TK11855: Part Name
F: SON3024-8 Package
TL: Tape&Reel, Left
-GH:
PB-Free&Halogen Fre
e
3,000
pcs.
/Reel
Block Diagram, Standard Application
3
2
1
Oscillator
Output Drive
Control
GND Ovp
EA
OUT
8
6
V
IN
Reference
Voltage
0.267V
0.6V
Error Amp
PWM Comp
7
SW
4
5
V
FB
EN PGND
Over Current
Detector
R
LED
12
Ω
L
15
μ
H
4.7
μ
FC
IN
I
LED
PGND
4
81
2
3
TK11855F
5
6
7
V
IN
GND
V
FB
E
A.OUT
SW
OVP
En
V
IN
on/off
SBD
2.2
μ
FC
OUT
0.22
μ
FC
EA
